Speed-controlled brake.



W. V. TURNER.

SPEED CONTROLLED BRAKE. APPLICATIDN nun IULY 13. 1916.

Patented NOV. 5, 1918.

MAM 1521f. l3

MAWEf/PA BIMME cm .v 2

I mvm'mm wafmvvi Turner rat i T lA llWl WALTER V. TURNER, 0F WTLTHNSJBU1M3, PENNSYLVANIA, .assreivcn TU T1111 WESTTNG HOUSE AIR BRANT? COMPANY,015 WTLMERDING, PENNSYLVANIA, A UUlEtlEONATTUN UTE PENNSYLVANIA.

Specification 01 Letters Patent.

SPEED-CONTROLLED BRAKE.

Patented Nov, 3, TATA,

Application filed July 13, 1916. Serial No. 109,053.

a citizen of the United States, residing at.

Wilkinsburg, in the county of Allegheny and State of Pennsylvania, haveinvented new and useful Improvements in Speed- Controlled ]Brakes, ofwhich the following 1s a specification.

This invention relates to fluid pressure brakes, and more particularlyto a brake apparatus for controlling the brakes accordin to the speed ofthe train.

Tt has heretofore been proposed to provide a brake apparatus adapted toapply the brakes with increased power in an emergency application, forexample, by supplylng fluid to the brake cylinder at a higher pressurethan in a service application of the brakes.

The higher the braking power applied, the greater will be the joltingeffect produced by suddenly applying the brakes, and while this effectWlll not be severe it the train speed is high, at lower speeds, thejolting becomes much more noticeable and is often very disagreeable topassengers. o

The principal object or my invention 18 to provide means controlled bythe speed of the train for varying the braking power in an emergencyapplication of the brakes, according to the speed of the train at thetime the brake application is made.

1n the accompanying draw1ng, the"s1ngle figure is a diagrammatic view,mainly in section, of a car brake apparatus embodying my invention.

In order to illustrate one application elf my invention, 1 have shown myinvention applied to the emergency portion oil" a brake equipment suchas covered by my prior Patent No. 1,131,971, dated Mar. 16, 1915, inwhich the emergency portion may comprise a casing 1 having a pistonchamber 2 containingan emergency piston 3 and avalve chamber 4:containing an emergency valve 5 adapted tobe actuated by said piston.

The piston chamber 2 is normally connected to the brake pipe 6 through apassage 7 controlled by a protection valve device A, and valve chamberA, which is connected by ipe 9 to a closed chamber 10, is charged romthe brake pipe through a teed groove 11 around piston 3.. a I Accordingto thepatent construction, an

emergency fluid pressure supply valve de vice'12 is provided whichcontrols commu nication from a source of high pressure sup ply, such asmain reservoir 13, throughpipe 1 1 and passage 15 to passage 16 and pipe17 leading to brake cylinder 18. I

The valve device 12 is normally held closed by a spring 19 and isadapted to be operated a by a valve mechanism comprising a piston 20.contained in piston chamber 21 havin a passage 25 leading to emergencyslide va ve 5, and a valve 22 adapted to be operated by piston 20 forventing fluid through a pas sage 23 from the spring side of theemergency supply valve device 12 to an atmospheric exhaust port 21-.According to a preferred form of my invention, there is interposed inthe supply pipe 14 a train speed controlled valve mechanism comprising acasing 26 having a valve chamber 27 connected to the main reservoir sideof pipe 1 1 and containing a slide valve 28 for controllingcommunication from the valve chamber 27 to the emergency valve side ofpipe 14:;

The valve 28 is provided with a downwardly extending stem 29 which iscarried by an operating member 30 adapted'to be shifted in one directionby a spring 31 and in the opposite direction according to the speed outthe train;

The speed control'mechanism may comprise ordinary speed governor balls32 adapted to be rotated by a. suitable operating connectionto arotating part vo1 the car, such as meshing gears 33 and 34:, the gear 31being secured to the car axle 35.

The centrifugal action of the governor balls 32 eflects the longitudinalmovement of a stem 36, this movement being preferably transmitted to themember 30 through a ball bearing 37, so'that the stem 36 can freelyrotate without rotating the member 30.

Th operation, the standard brake pipe pressure normally maintains theprotection valve'tl in the open position shown in the drawing, so thatthe piston chamber 2 and valve chamber 1 are normally charged with tluidunder pressure and a spring 38 mainvalve 28 to a varying extentaccording as the speed 01 the train exceeds a certain minimum rate, 7

It will thus be seen that if the speed of the train is less than thepredetermined minimum rate, the valve 28 will remain in the positionshown in the drawing. entirely cutting off communication from the mainreservoir 13 to the emergency valve mechanism.

If under the above conditions. the brake pipe pressure is reduced to apredetermined degree at which an emergency application is effected, theprotection valve 8 will be shifted to its lower seat, so as to ventfluid from piston chamber 2 and thus effect the movement of theemergency valve device to emergency position.

In this position, the usual quick action valve device 45 is operated bythe connection of passage 41 through cavity 42 with a fluid pressuresupply passage 43, so that a local reduction in brake pipe pressure iselfected.

Passage 25 is also connected to a port 44, so that fluid under pressureis supplied from valve chamber 4. to piston chamber 21. The piston 20 isthen operated to open valve 22 and vent fluid through passage 23 fromvalve device 12, so that said valve device opens communication frompassage 15 to brake cylinder passage 16, but since comn'iunication isnow out off from the main reservoir 13, the opening of the valve device12- will have no effect and consequently the brake cylinder pressurewill be that due to the usual operation of the service applicationportion of the brake apparatus, corresponding with the action of anordinary triple valve device, or as described in my hereinbeforementioned patent, but which it isnot considered necessary to illustratein the present case.

If, however, the train speed exceeds the minimum rate, the centrifugalaction of the governor balls 32 will cause the movement of. stem 36, sothat member 30 is actuated to open the valve 28, and this opening willbe increased in propoit-ion to the increase in' speed of the train, sothat the emergency braking power will bear a relation to the speed ofthe train-and thus provide for so regulating the braking pressure thatsevere jolting effects Will be avoided in stopping the train.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. In a fluid pressure brake, the combination with a brake pipe andmeans operated upon a sudden reduction in brake pipe pressure foreffecting an emergency application of the brakes With increased power,of a train speed controlled device for varying the braking power in anemergency application to correspond with the speed of the train.

2. In a fluid pressure brake, the combiing the emergency braking powerto cori'espond with speeds less than a predetermined lllilxlllllllll.

3. In a fluid pressure brake. the combination with means adapted toeffect an emergency application of the brakes at a higher brake cylinderpressure than in a service application, of a train speed controlleddevice for varying the opening through which fluid is supplied to thebrake cylinder in an emergency application according to the speed of thetrain.

at. In a fluid pressure brake. the combination with means adapted toeffect an emergency application of the brakes at a higher brake cylinderpressure than in a service application. of a train speed controlleddevice adapted at a predetermined maximum speed .to permit full flow offluid to the brake cylinder in an emergency application and to reducesaid floW as the train speed is reduced.

5;In a fluid pressure brake, the combination With means adapted toeffect an emergency application of the brakes at a higher brake cylinderpressure than in a service application, of a train speed controlleddevice adapted at a predetermined maximum speed to permit full flow offluid to the brake cylinder in an emergency application, to reduce theflow as the train speed is reduced and finally at a predeterminedminimum speed to entirely cut off said flow.

6. In a fluid pressure brake, the combination with a source of fluidpressure, a brake cylinder, and an .emergency valve mechanism operatingto supply fluid from said source to the brake cylinder in an emergencyapplication of the brakes, of a train speed controlled device forcontrolling communication from said source through the emergency valvemechanism to the brake cylinder and adapted to reduce the flow 0f fluidas the train speed is reduced.

7. In a fluid pressure brake, the combination with a main reservoir, abrake cylinder. and an emergency 'valve device for supplying fluid fromthe main -reservoir to the brake cylinder in an emergency application ofthe brakes, of a valve for controlling the rate of flow from the mainreservoir through said emergency valve device to the brake cylinder anda train speed'controlled mechanism for operating said valve.

In testimony whereof I have hereunto set my hand.

WALTER V; TURNER.

